How to Make It
In a spice grinder, combine the granulated sugar and the lemon zest. Pulse until well combined and set aside.
In the bowl of a stand mixer fixed with the paddle attachment, combine the flour, butter, salt and baking soda, and beat on the lowest speed until it resembles cornmeal. Add the lemon-sugar mixture, heavy cream and vanilla and beat until the ingredients are just clumped together without overmixing.
Divide the dough in half and roll each half into a log about eight inches long. Wrap each log in plastic wrap and refrigerate for at least 30 minutes.
Preheat the oven to 350º. Unwrap one log and slice it into 1/4-inch-thick rounds. Place slices on a cookie sheet about two inches apart. In between batches, keep the remaining dough refrigerated. Bake for 10 minutes or until edges are lightly browned. Allow the cookies to cool for several minutes before transferring to a wire rack to cool completely.